The invention is particularly concerned with valved closures, in which the closure includes a valve device which opens the outflow path for dispensing and closes it when dispensing pressure is relieved.
Crossed-slit silicone valves are widely used for this purpose: an inwardly convex silicone rubber dome with crossed slits is mounted in the outlet opening of the closure. Under dispensing pressure it inverts (bulges outwardly) and the slits open up as a flow opening. When pressure is relieved the rubber dome flips rapidly back in to its original form, closing the slits. Flow is immediately cut off and dripping prevented, while on recovery compensation air can enter and suck-back of residual product at the outlet may also be achieved. Another known drink bottle valve has a slit rubber outlet piece in which the slit gapes open when the user bites on the tube. However, while these slit rubber valves are effective, the rubber is expensive and neither recyclable nor degradable.
Our aim herein is to provide new and useful types of valved dispensing closure, and corresponding dispensers, especially with a view to providing a closure that requires neither special elastomer materials nor auxiliary springs and the like, and which in preferred embodiments is suitable for a drinks dispenser. A corresponding drink dispenser comprising the closure in combination with drink container is an aspect of our proposals.